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Updated: Aug 14, 2026
07:27
Quantifying Microorganisms at Low Concentrations Using Digital Holographic Microscopy (DHM)
Published on: November 1, 2017
Technique for Estimating Low Numbers of a Bacterial Strain(s) in Soil
1Microbiology Program, The Pennsylvania State University, University Park, Pennsylvania 16802.
Applied and Environmental Microbiology
|April 1, 1987
Summary
This study introduces a new method to accurately count low bacterial numbers in soil using bacteriophage detection. This technique enhances microbial enumeration for environmental and agricultural research.
Area of Science:
- Microbiology
- Environmental Science
- Soil Science
Background:
- Accurate enumeration of low bacterial populations in soil is crucial for understanding microbial ecology.
- Traditional methods may lack sensitivity for detecting bacteria present in scarce numbers.
Purpose of the Study:
- To describe and evaluate a novel technique for estimating the most probable number of bacterial cells in soil samples.
- To assess the applicability of this method for quantifying low bacterial densities, specifically for gram-negative bacteria.
Main Methods:
- The technique utilizes the specific response of bacteriophages when incubated with soil dilutions in nutrient broth.
- A known quantity of bacteriophage is added to soil dilutions to detect the target bacterium.
Main Results:
- The method provides reliable most probable number estimates for bacterial strains present in low concentrations in soil.
- The technique demonstrated effectiveness when evaluated for gram-negative bacteria.
Conclusions:
- This bacteriophage-based assay offers a sensitive approach for quantifying low bacterial numbers in soil.
- The method holds potential for applications in soil microbiology, environmental monitoring, and agricultural diagnostics.
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